Streptococcal pharyngitis is a frequent infection in school aged children. This infection is caused by multiple strains of a single species of Lancefield group A streptococci, Streptococcus pyogenes. In addition to pharyngitis, the organism may cause pyogenic infections of the upper and lower respiratory system (eg. otitis media, pneumonia) as well as systemic infections such as septicemia, septic and reactive arthritis and soft tissue infections,and toxigenic infections such as scarlet fever and toxic shock syndrome.